The U.S.-Israeli war with Iran has put a chokehold on the vital Strait of Hormuz waterway, sending fuel prices soaring and imperiling global stocks of critical resources, including fertilizer.
Since the start of the war, global prices for nitrogen fertilizer have surged, sending agricultural officials around the world interference to offset costs and consolidate supplies before shortages hit food crops. Between February, when the war broke out, and mid-May, the United States urea pricea common fertilizer, rose from about $460 per ton to nearly $600 per ton.
The reason fertilizers are so endangered has to do with how they’re made: To make urea, for example, U.S. producers often rely on natural gas as both an ingredient and a fuel source, says Asim Biswas, a professor in the school of environmental sciences at the University of Guelph in Ontario. Although the United States does not rely on natural gas from the Middle East, approximately 20% of the world’s liquefied natural gas passes through the Strait of Hormuz, and the disruption of this supply has caused prices to rise globally. The consequence of the fertilizer effect is increased food costs – and perhaps even food shortages.
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“All of this uncertainty is happening globally in farmers’ fields,” Biswas says, “and we’re going to see it, as the general public, on our grocery bill and on our plate.”
Why do we need fertilizer?
To make urea fertilizer, manufacturers use an energy-intensive method called the Haber-Bosch process, which uses methane, the main component of natural gas, and atmospheric nitrogen to make ammonia. This ammonia is then converted into urea.
Faced with soaring fertilizer and energy costs, it may make sense to ask, “Why not just use less?” Without synthetic nitrogen fertilizer, researchers estimate farmers could only feed about half of the world’s approximately eight billion people.
For farmers, Biswas compares the need for fertilizer to a salary: your salary is the input and your expenses are the output. A healthy forest ecosystem can balance the “inputs” of organic matter and nutrients with the slow “output” of tree growth. But a farmer harvesting 150 bushels of corn a year from a field must replenish the nutrients to be able to grow corn again the following year. “We need this [fertilizer] to input; otherwise, production will deplete the bank account,” says Biswas.
“In many cases, when there isn’t enough fertilizer, farmers start to think, ‘Oh, maybe I should put less fertilizer.’ As soon as we use less, production suffers,” he adds.
Simply put, rising agricultural costs could mean less food: in March, the United Nations World Food Program (WFP), estimated that the rising cost of energy and fertilizer following the war in Iran risks plunging an additional 45 million people into “acute food insecurity”.
What does this mean for food costs?
Spring is planting season for many farmers in the Northern Hemisphere, so the timing of the war’s effects on fertilizer puts growers in a difficult position: They must balance using expensive materials with the ability to try new planting methods or new crops, or even forgo a planting season altogether.
According to an April 2026 survey by researchers at the Purdue Center for Commercial Agriculture, more than 65 percent of farmers in the United States believe that the conflict in Iran would have a “negative” or “very negative” effect on their net income. Farmers in low-income countries are particularly vulnerable. While rich countries like Canada and the United States can subsidize the cost of fertilizer, many countries, such as in Africa and parts of Latin America, cannot, Biswas says.
In 2022, farmers felt similar pressures after Russia’s invasion of Ukraine, which also disrupted energy and fertilizer prices. But at the time, crop prices like corn reached “record” levels, which helped farmers offset the cost of higher production, says Joana Colussi, an assistant professor in the department of agricultural economics at Purdue University and leader of the April 2026 survey. That’s not the case today, so prices will rise without any respite.
In response to high fertilizer costs, some farmers may shift to crops that require less nitrogen to grow reliably. Soybeans, for example, can absorb nitrogen directly from the atmosphere through a symbiotic relationship with nitrogen fixer Rhizobium bacteria that form “nodules” on the roots of legumes, Biswas explains.
But if too many farmers switch to soybeans instead of, say, corn, the price of soybeans will fall. Likewise, if some farmers take the risk and stick with expensive, nitrogen-intensive corn, a smaller supply could cause the price of corn to rise. This equals higher grocery bills.
Farmers have little control over these dynamics. “We say farmers don’t set prices,” says Biswas. They are the ones who take the prices.
Can we produce more fertilizer in the United States?
To address some of these pressures, policymakers could consider expanding fertilizer production in the United States, said Farzad Taheripour, a research professor in the department of agricultural economics at Purdue University. Although the country has no shortage of natural gas, it could use more of its industrial capacity to convert that natural gas into nitrogen fertilizer.
“In the United States, to help the agricultural sector and guard against changes in the energy market outside the United States, we need to increase our capacity to produce more fertilizer from domestic sources – natural gas,” says Taheripour, adding that this could be “a worthwhile investment” for the United States to consider.
In theory, genetically modified crops – which, for example, require less nitrogen to grow – could also help, some experts say. But this approach “does not replace fertilizer,” says Biswas. Although biotechnology can improve a plant’s ability to obtain nutrients from its environment, it does not eliminate basic needs for nutrients such as nitrogen.
Another solution might simply be to think differently about fertilizer, Biswas says. In a comment In Nature Earlier this month, he and his co-authors argued that governments around the world should view fertilizer as a “crucial part of the food system,” not just a commodity. Countries could consider creating fertilizer stocks similar to strategic oil reserves – an approach the European Union advocates. currently considering—as well as more efficient and effective application methods low carbon fertilizer.
“Unless governments view fertilizer production as strategic infrastructure,” write Biswas and his co-authors, “the world will continue to move from energy shock to crop failure.”
